This invention relates generally to methods and apparatus for detecting radiation in a Computed Tomography (CT) imaging system, and more particularly to scintillator arrays used in a CT imaging system.
In at least some CT imaging system configurations, an x-ray source projects a fan-shaped beam that passes through the object being imaged, such as a patient. The beam, after being attenuated by the object, strikes and is detected by an array of radiation detectors. These radiation detectors typically include a collimator for collimating x-ray beams received at the detector, a scintillator that is adjacent to the collimator, and photodetectors that are adjacent to the scintillator.
At least one known detector array includes a two-dimensional array of scintillator cells, wherein each scintillator cell has an associated photodetector. When manufacturing these types of scintillator cells, an epoxy material is typically used to cast the scintillator cells into a block having specified dimensions. To facilitate reflectivity and to reduce cross-talk between adjacent detector cells, the cast reflector mixture includes a material that has a relatively high refractive index, such as TiO2. Therefore, the cast reflector mixture facilitates confining light that is generated in the scintillating material by impinging x-rays within the detector cell in which it is generated. However, when a failure is detected within either the scintillator or the cast reflector mixture between the scintillators, the entire scintillator assembly may have to be replaced. Accordingly, casting the reflector mixture between the scintillators can result in an increase in the manufacturing costs of the imaging system.